a) It will not hurt that much (more towards the end than anything) as calf's are a pretty meaty/muscular area to get tattoo'd. you're not dealing with sensitive 'fleshy' areas or directly over bone so it's a good place to get a first one.
b) a b/w tattoo that size should NOT take any longer than 2 hours
c) no less than $40 imo, but it really depends on how happy you are with the final product